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| Mirrors > Home > ILE Home > Th. List > freq2 | GIF version | ||
| Description: Equality theorem for the well-founded predicate. (Contributed by NM, 3-Apr-1994.) |
| Ref | Expression |
|---|---|
| freq2 | ⊢ (𝐴 = 𝐵 → (𝑅 Fr 𝐴 ↔ 𝑅 Fr 𝐵)) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | frforeq2 4435 | . . 3 ⊢ (𝐴 = 𝐵 → ( FrFor 𝑅𝐴𝑠 ↔ FrFor 𝑅𝐵𝑠)) | |
| 2 | 1 | albidv 1870 | . 2 ⊢ (𝐴 = 𝐵 → (∀𝑠 FrFor 𝑅𝐴𝑠 ↔ ∀𝑠 FrFor 𝑅𝐵𝑠)) |
| 3 | df-frind 4422 | . 2 ⊢ (𝑅 Fr 𝐴 ↔ ∀𝑠 FrFor 𝑅𝐴𝑠) | |
| 4 | df-frind 4422 | . 2 ⊢ (𝑅 Fr 𝐵 ↔ ∀𝑠 FrFor 𝑅𝐵𝑠) | |
| 5 | 2, 3, 4 | 3bitr4g 223 | 1 ⊢ (𝐴 = 𝐵 → (𝑅 Fr 𝐴 ↔ 𝑅 Fr 𝐵)) |
| Colors of variables: wff set class |
| Syntax hints: → wi 4 ↔ wb 105 ∀wal 1393 = wceq 1395 FrFor wfrfor 4417 Fr wfr 4418 |
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-ia1 106 ax-ia2 107 ax-ia3 108 ax-io 714 ax-5 1493 ax-7 1494 ax-gen 1495 ax-ie1 1539 ax-ie2 1540 ax-8 1550 ax-10 1551 ax-11 1552 ax-i12 1553 ax-bndl 1555 ax-4 1556 ax-17 1572 ax-i9 1576 ax-ial 1580 ax-i5r 1581 ax-ext 2211 |
| This theorem depends on definitions: df-bi 117 df-tru 1398 df-nf 1507 df-sb 1809 df-clab 2216 df-cleq 2222 df-clel 2225 df-nfc 2361 df-ral 2513 df-in 3203 df-ss 3210 df-frfor 4421 df-frind 4422 |
| This theorem is referenced by: weeq2 4447 |
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